Magnetometers have long been used for measuring the intensities of magnetic fields. Magnetometers are available which measure magnetic field strength using both mechanical and electrical techniques. One type of electronic magnetometer, known as a fluxgate magnetometer, is frequenctly used as a compass to provide an output representative of the orientation of the magnetometer with respect to the magnetic field of the earth.
While numerous circuits are known for implementing fluxgate magnetometer compasses, these circuits frequently require an appreciable amount of power. Especially where a magnetometer must be capable of operating off a battery or other low-capacity power supply, conventional magnetometer circuits are frequently not suitable.